Story highlights

Candidate keeps up attacks on Mitt Romney during address to supporters

Upending the conventional wisdom that he would have a tough night on Super Tuesday, Rick Santorum beat expectations with at least three victories.

The former Pennsylvania senator won Tennessee, Oklahoma and North Dakota. And in Ohio, Santorum lost by a slim margin in a race that came down to a difference of about 10,000 votes, according to the Ohio secretary of state's unofficial tally.

Throughout the night, Santorum's aides repeatedly approached reporters to raise questions about Romney's viability as a general-election candidate.

"I'll be interested to find out if Mitt Romney has won a Southern state today," Santorum adviser John Brabender quipped to reporters.

"If somebody can't do well in the South, then they shouldn't be running at all," Brabender said referring to Romney's losses in Georgia and Tennessee.

Brabender says the campaign wants a one-on-one matchup with Romney, suggesting Santorum could win the nomination with Gingrich out of the race.

Earlier Tuesday, Santorum adviser Hogan Gidley said the former senator from Pennsylvania is willing to take the race all the way to the convention.

"If we all go to the convention with a certain amount of delegates, and we have to figure something out at the convention, so be it," Gidley told reporters at the campaign's Super Tuesday party headquarters.

Gidley's comments came in response to one of the chief arguments made by Romney's advisers, who predict the former senator will be too far behind in the delegate count to catch up and clinch the nomination after Super Tuesday.

"He's got to get to 1,144, too," Gidley snapped back in a reference to the number of delegates needed to secure the nomination.

"He wants us out because he can't get there," Gidley added, referring to Romney.

It's unlikely Santorum will win the most delegates in the crucial Super Tuesday battleground. The campaign failed to file the necessary paperwork to pick up delegates in areas of Ohio where Santorum was favored to come out on top.

Gidley shrugged off the mistake, saying Santorum is not the "establishment candidate."

On Wednesday, Santorum is scheduled to move on to the next contests, with stops expected in Kansas, Mississippi and Alabama.